Welding Weldox

SSAB produces high strength steels that conform to most international and national standards. Our high strength steels are marketed under the Weldox brand name.

Weldox has been developed to provide excellent weldability, combined with high strength and toughness. The ore-based metallurgy and advanced processing in the steel shop ensures very low contents of residual elements in the steel. Weldox high strength steels have excellent bendability and machinability properties. Due to the high strength of the steel, the end products can be strong but lightweight, which allows for substantial reductions in the cost of materials, welding and transport. Good flatness and fine surface quality are also distinguishing features of Weldox plate.

Weldox high strength steel is produced in thicknesses ranging from 4 to 130 mm, and with guaranteed yield strengths between 700 MPa and up to 1300 MPa. The flexible production system enables us to deliver plate with tailored properties to suit the customer’s requirements. We can supply plate in thermomechanically rolled or quenched and tempered condition. In addition, most Weldox steels can be supplied with guaranteed impact toughness at temperatures down to –60°C.

Preheat and interpass temperatures

The right preheat and interpass temperature is important in order to avoid hydrogen cracking.

Influence of alloying elements on the choice of preheat and interpass temperatures

A unique combination of alloying elements optimizes the mechanical properties of Weldox and Hardox. This combination governs the preheat and interpass temperature of the steel during welding, and can be used to calculate the carbon equivalent value. The carbon equivalent value is usually expressed as CEV or CET in accordance with the equations below.

The alloying elements are specified in the inspection certificate of the plate and are stated in percent by weight in these formulas. A higher carbon equivalent usually requires a higher preheat and interpass temperature. Typical values of carbon equivalents are given in our product data sheets.